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When to Plant Parsley in Sanders County, MT

Sanders County, Montana Zone 6a May

May in the garden — Sanders County, Montana

May is a pivotal month for Sanders County, Montana gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 24
Avg. first frost September 13
Soil temp (4") 39°F
Watering High
Pest pressure Low
Daylight 14.9 hrs
  1. Move parsley from tray to bed

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

  2. Plant parsley from seed, right in the garden

    Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.

Before June arrives, get these ready
  • Starting indoors: parsley

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Parsley is a biennial herb available in flat-leaf (Italian) and curly varieties. It is a nutritional powerhouse rich in vitamins C and K and adds fresh flavor to countless dishes.

Sanders County, Montana is in USDA Zone 6a. The average last spring frost is May 24 and the first fall frost is September 13, giving you a growing season of approximately 112 days.

At an elevation of 5,775 feet, Sanders County receives approximately 16.4 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Parsley during the growing season. With low rainfall, drip irrigation is essential for growing Parsley successfully. Mulch heavily to conserve soil moisture.

Sanders County, MT (Zone 6a) Short season
112 days
Last Spring Frost May 24
112 growing days
First Fall Frost September 13

Sanders County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 7 Transplant: May 5 🍅 Harvest: Jul 7 – Sep 8
Recommended (50%) ✗ May not fit
Start indoors: Apr 19 Transplant: May 17 🍅 Harvest: Jul 19 – Sep 20
Safe Start (90%) ✗ May not fit
Start indoors: May 23 Transplant: Jun 20 🍅 Harvest: Aug 22 – Oct 24

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Sanders County

How your county's soil matches Parsley's growing requirements.

Soil pH

Your soil pH (6.3–7.9) is more alkaline than Parsley prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Sanders County is excellent for Parsley — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Parsley.

How to Plant Parsley

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Parsley

2
successive plantings in your 112-day season

Sow every 6.9 weeks. Last sowing by Jun 25 to harvest before frost.

For a dedicated fall crop, sow by Jul 05.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Parsley

Parsley needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Parsley Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 1.7" 0" ❄️ Dormant
May 2.6" 1.8" 0.8" 💧 Light watering
Jun 2.6" 1.3" 1.3" 🚿 Regular watering
Jul 2.6" 1.5" 1.1" 💧 Light watering
Aug 2.6" 1.7" 0.9" 💧 Light watering
Sep 2.6" 1.4" 1.2" 💧 Light watering
Oct 1.4" 0" ❄️ Dormant
Nov 1.2" 0" ❄️ Dormant
Dec 1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Sanders County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Parsley Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Parsley needs ~1,068 GDD — county provides 1,708 GDD Excellent fit

Parsley Planting Timeline — Sanders County, MT

Parsley Planting Calendar

Activity When Date Range
Start Indoors April 19 Apr 19 – May 3
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 10 May 10 – May 31
Harvest July 19 Jul 19 – Sep 20
Fall Sowing July 5 Jul 5 – Jul 19

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Start Indoors Transplant Outdoors Direct Sow
June
July Fall Sowing Harvest
August Harvest
September Harvest
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.6"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

112 days in Sanders County

Growing Tips for Parsley in Sanders County

Direct sow Parsley outdoors after May 24 in Sanders County when soil has warmed and frost danger has passed.

Common pests for Parsley in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Soak seeds overnight as germination is slow. Harvest outer stems first to keep plants productive. Parsley attracts swallowtail butterflies.

Companion Planting

Good Companions

Avoid Planting Near

  • Mint
  • Lettuce

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Parsley in Sanders County, MT?

Sanders County is in Zone 6a with an average last frost of May 24. Plan your Parsley planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sanders County, MT?

Sanders County, Montana is in USDA Hardiness Zone 6a. The average last spring frost is May 24 and first fall frost is September 13.

🌱

Your Sanders County Garden Planner — Free

A 24-page printable planner built for Sanders County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Sanders County, MT. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.